At present, the principle identification technique in the returnable and refillable bottle market is by applied color label, also known as ACL. This technique employs a screen-applied colored ceramic frit fused permanently to the surface of the glass in one or more colors on the body and/or neck of the container. The ACL is applied by the glass manufacturer, thus eliminating the need for in-line labeling equipment or costly paper label removing equipment at developer locations. Although the graphics that can be achieved within the restrictions of the ACL process are limited to relatively simple line work, the results have been generally acceptable to the bottling industry. ACL treated glass bottles represent a relatively high initial cost. This cost can be justified when cycle time, trippage, sorting and cleaning costs are acceptable to the individual developer.
Recently, changes have taken place in equipment, in glass pricing and in other areas that have created a need for a system to replace ACL returnable and refillable bottles. Developments have taken place with plastic labels and with heat shrinkable sleeves which might lead in the direction of suitable replacements for ACL.
The Shank U.S. Pat. No. 3,604,584 reveals a method for protecting jars and bottles from abrasion by heat shrinking a thermoplastic material around a portion of the glass article. Thus, for example, a protective sheet or tube made from a thermocontractive polyvinyl chloride film having a thickness of about 3 mils. can be used. The diameter of the sheet is slightly greater than the diameter of the bottle so that the tube can be easily slid over the bottle but when shrunk, will tightly encircle the bottle. The shrinkage can be effected by immersing the tube and bottle in a bath of water which is heated to approximately 180.degree. F.
The Beyerlein U.S. Pat. No. 3,542,229 deals with a plastic bottle having a shrunk stregthening band. The bursting strength of a bottle of, for example, thermoplastic material is increased by applying about the body of the bottle a shrunk-on band of stretchable heat shrinkable plastic film which is under tensile stress and prestresses the bottle body. The stretched band is specifically made of polyvinyl chloride which makes it possible to transfer the advantages of high creep rupture strength to the bottle which is involved. This patent also discloses that it is possible to print on the inner side of the band which is transparent and that the body of the bottle itself may also be printed upon since the band will protect the printing from scratching or other damage.